const myArray = new ArrayBuffer(0x800) // populated from elsewhere
const readInt32 = (array, index) => {
  const typedArray = new Uint32Array(array, index, 1)
  return typedArray[0]
}
const writeInt32 = (array, index, value) => {
  const typedArray = new Uint32Array(array, index, 1)
  typedArray[0] = value
}

const sourceAddress = readInt32(myArray, 0)
const targetAddress = readInt32(myArray, 4)
const value = readInt32(myArray, sourceAddress)
writeInt32(myArray, targetAddress, value + 1)